A magnetic random access memory (MRAM) chip used as a nonvolatile semiconductor memory device controls operations, such as writing, reading and data storage, utilizing magnetization of a magnetoresistive element. Accordingly, if the magnetization of the magnetoresistive element is influenced by an external magnetic field passing through the MRAM chip, the operations may well vary. In view of this, it is desirable to block the external magnetic field using a magnetic shield layer so that the external magnetic field does not enter the MRAM chip.